Service Brakes Problems of Mercedes Benz C300 - part 1

The contact owns a 2008 mercedes-benz C300. The contact stated that while depressing the brake pedal, attempting to stop, the vehicle failed to respond as intended and causing the contact to drive through a stop sign, then merge onto the interstate independently. The driver's side rear tire was leaking brake fluid. The check brake system warning light illuminated. The vehicle was towed to a dealer, where it was diagnosed that the brake line was corroded. The vehicle was repaired under warranty for the subframe prior to the failure; however, the brake lines were not covered and needed replacement. The vehicle was then towed to an independent mechanic where the brake lines were pending replacement; however, the mechanic was waiting for parts. The manufacturer was notified of the failure and offered no assistance. The approximate failure mileage was 164,000.

See all problems of the 2008 Mercedes Benz C300 🔎.

Certified mercedes dealership confirmed that the subframe of my 2008 C300 is rusted and needs to be replaced which is under warranty. However, they are unwilling and do not acknowledge that the brake lines are also rusted and need to be replaced which is caused by the rusted subframe. I first consulted my local mechanic shop who specializes in mercedes repairs, and he told me about the issues of the corroding subframe and the rested brake lines. He also mentioned that he has helped and directed many mercedes owners to call mercedes customer service to voice my concerns as well as confirm the warranty of the subframe.

Went to the mercedes dealership service department to replace the rear subframe that suddenly broke while I was driving due to extreme rust/corrosion. The dealership stated that it was being covered under the extended warranty due to the recall related to the rust/corrosion issue with the subframe. I was advised by the mechanic that the brake lines will need to be replaced due to extreme rust/corrosion in the rear at the same exact location of the rear subframe, making the vehicle very dangerous to drive because the brake lines could break at any moment and cause sudden brake failure. I was quoted a very significant amount to replace the rusted brake lines and per the dealership, it will not be covered under any extended warranty and/or recall.

See all problems of the 2009 Mercedes Benz C300 🔎.

Rear subframe rust out and rear passenger brake line corrosion. The entire subframe has to be taken apart in order to reach the brake line. The vehicle is due to get the rear subframe replaced as part of the warranty extension. The brake lines are not covered. Took it into Mercedes Benz dealership in santa fe, nm. They will not even touch it because they don't even know how repair it. Also they never done this type of work.

See all problems of the 2010 Mercedes Benz C300 🔎.

On several instances of breaking, my 2013 Mercedes Benz C300 pulls hard to the right and becomes very unstable. I assumed it was a brake problem by the way the car drove. I took it to my mechanic, who immediately identified the rear subframe had rusted so much that a control arm had broken loose from the subframe. The rear subframe acts as a foundation for the rear suspension and holds the backend together. Fortunately I was able to get this diagnosed prior to a serious accident. The car gets very unstable, especially at higher speeds, when braking. There are no warning lights that will catch this. This problem absolutely places both passengers and other cars on the road at risk of a collision when braking, especially on the highway at higher speeds. I am going to contact a local Mercedes Benz dealer to evaluate replacement of the damaged parts to ensure the car is safe to drive following repair. Based on the links below, it sounds like a known issue at Mercedes Benz. I was never notified of any issues or from prior service visits, or via mail notice from the manufacturer. My mechanic was shocked, to say the least. Hoping mb will take care of this dangerous problem without hassle. See: [xxx] [xxx] [xxx] information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

See all problems of the 2013 Mercedes Benz C300 🔎.

The contact owns a 2011 mercedes-benz C300. The contact stated that while driving at an undisclosed speed, the brake pedal was depressed and almost went all the way to the floorboard, and the vehicle failed to stop as needed, requiring an increased effort to bring the vehicle to a complete stop. No warning lights were illuminated. The vehicle was taken to the dealer but was not yet diagnosed. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was unknown.

See all problems of the 2011 Mercedes Benz C300 🔎.

The subframe has developed extensive rust and corrosion, which I believe is a result of faulty manufacturing. This corrosion has severely compromised the structural integrity of the subframe, posing a serious safety risk. The corrosion appears to be inherent to the materials or design used in the manufacturing process, leading to the rapid deterioration of the subframe. There are also no warning lights or failure indicators for this issue. As a result, the subframe is at risk of collapsing, which could cause catastrophic failure of the vehicle's suspension and steering systems. This situation creates an immediate danger to both the occupants of the vehicle and others on the road.

See all problems of the 2012 Mercedes Benz C300 🔎.

The right rear brake line had rusted out and caused complete brake failure while driving. If this occured at highway speeds it could have resulted in serious injuries. A search has shown this is widespread with the C300 and other mercedes vehicles and although mercedes has acknowledged this in other vehicles it has not done so for the C300. This is a potential for serious bodily injury and should be addressed.

Brake line corrosion.

Rear brake line rusted through land leaked all the break fluid rendering the vehicle unsafe to drive due to the complete failure of the breaking system. The location of the break line corrosion is above the rear differential and next to a retainer clip.

The brake lines in this car rot very early in life span. This is a severe issue as no one would know unless car is brought in for repair. There is already a extended warranty for subframe rotting for my C300 and several other models and years . Both of these should be repaired due to poor manufacturing not just the subframe. Both of these issues even independently put everyone on the road at risk of potential failure. Car has been brought in for repair and has been pointed out to me both by independent party and Mercedes Benz dealership in my area. There are no warnings also multiple claims for both rusting and rotting.

Took my car for a doorknob repair and was told the whole subframe is rotted. They told me not to drive the car on the highway. The car brakes very hard to the right and always goes right while making cranking noises. Car feels very unsafe. I paid a lot of money for this and own a 2012 C300 4matic.

The brake lines have corroded in multiple places causing brake fluid to leak, potentially creating a safety risk had the problem not been immediately observed and corrected. An independent service center confirmed the problem and replaced all the brake lines and hoses. There were no warning lamps or signals. A puddle of brake fluid under the car was the first indication of a problem.

This is a low mileage car with odometer reading of 25668 (less than 2000 miles per year), used sparingly and always parked in the garage. On 05/07/2024 I noticed brake fluid flowing from the left rear side of the car; on examination this seemed to come from the flexible hose that connects the brake fluid line to the brake caliper. I called my mercedes-benz (mb) dealer and arranged for further inspection and service. The technician identified that the brake fluid lines to the rear were both totally corroded and in need of immediate replacement. Since the lines were embedded behind the subframe it necissated lowering the subframe to access. Other parts were also severely corroded and required replacement. (see attached pdf of invoice) the total cost of the repair was $4,592. 93. The dealership applied a discount of $150. 00 to this for an amount due of $4,442. 93. As an engineer, I believe the material used for the brake fluid lines were unsuitable and furthermore were unprotected for the harsh environment experienced under the car, and I believe mb with all their experience in automobiles manufacturing over the years clearly should have known and forseen this fact; I do believe that mb is responsible for this premature failure of the brake lines of my car aven driven only 25,666 miles to date. I am therefore requesting NHTSA to require mb to reimburse me for the unnecessary expense of the costly repairs. It is only fortunate that this failure was identified in my garage and not on the highway. Please advise me of your resolution. Thank you.

The contact owns a 2013 mercedes-benz C300. The contact stated while pulling into a parking space and depressing the brake pedal, the vehicle accelerated unintendedly. There was no warning light illuminated. The contact stated that she depressed the brake pedal but the vehicle failed to respond. The contact stated that while the vehicle was approaching a building ahead, she veered to the right and hit the front bumper of an occupied vehicle. The vehicle then drove over the side walk. The contact stated that while approaching the end of the side walk, she veered to the right and the vehicle stopped after a hundred feet. The air bag did not deploy. There was no injury sustained. A police report was filed. The vehicle was towed to an auto collision repair shop. The dealer and the manufacturer were not notified of the failure. The vehicle was not diagnosed or repaired. The failure mileage was approximately 23,032.

On 2/17/24 the vehicle was parked in front of my house. There is a slight grade. The vehicle had been parked for approximately 1 hour when my neighbor called me to tell me that the vehicle had rolled down the hill and into his storage building. The vehicle rolled on its own. I have video evidence that no one was in or around the car at the time of this occurrence. I also, have 2 eyewitnesses who can corroborate this story. Due to safety concerns, I immediately returned the vehicle to mercedes. I have . Mov files and pictures jpeg that will not upload for some reason.

See all problems of the 2023 Mercedes Benz C300 🔎.

On the afternoon of February 6, 2024, as I was turning into my driveway to park in front of the garage, my car unexpectedly accelerated despite my foot being on the brake pedal. Despite my attempts to brake, the pedal didn't respond, causing the car to collide with the garage door and subsequently damage storage shelves and containers inside. My mother and two brothers were passengers, returning from my mother's doctor appointment, and she became trapped inside due to the garage door collapsing onto the car. Emergency services were called, and both the fire department and police assisted in freeing my mother from the vehicle. However, the police did not file an accident report since it occurred on private property. Subsequently, I contacted my insurance agent, and the car was towed to a repair shop recommended by the dealer. Today, I was informed by the repair shop that the damages are extensive enough for the car to be considered totaled by the insurance company. Fortunately, the incident did not occur while driving on the freeway or public roads earlier that day, potentially averting a more serious accident. Nevertheless, the ordeal has caused considerable stress and sleep loss for all involved. I have since reached out to the repair shop and dealer to conduct a thorough diagnostic analysis to determine the cause of the malfunction. I've requested copies of the data captured by the on-board diagnostics (obd) system and event data recorder (edr), emphasizing that this data should not be deleted without my consent. However, I am uncertain about the next steps if the insurance company removes the car from the repair shop and how to access the requested data. Upon researching online, I've discovered numerous similar cases involving mercedes-benz cars, with over 20 incidents reported and 11 specifically concerning the same model as mine.

See all problems of the 2019 Mercedes Benz C300 🔎.

The esp®, or electronic stability control system can put the car into limp mode unexpectedly. Say you are driving on route 66 going 50 mph. The esp system can turn off if a wheel speed sensor or yaw sensor is on the way out. This causes the car to suddenly dramatically brake and limit speed to 5 mph on the highway. Risk of high speed rear end collision and mortality to the driver.

While driving past, close proximity or even going 30-40mph on a local road or even 60-70 on a highway the break assist function will repeatedly beep, and most times it will stop my car for me. This occurs also, when there are no cars near me! it’s very sudden, and unpredictable. On more occasions than few, if I’m driving in the middle of a 3- lane road, and cars are stopping in the far right lane, or making a turn my break assist will malfunction and automatically break. Multiple occasions I feared that a car may rear-end me. It happens alot. Very scary. This has been occurring for more than 2 years.

See all problems of the 2016 Mercedes Benz C300 🔎.

My brake line is corroded and needs replacing at a cost of $3500. 00. I have an extended warranty on the rear subframe due to a recall; however, mercedes will not cover this costly repair. I was informed by service advisor that I could still drive car with extra caution, as there are no leaks.

On Tuesday, the steering wheel failed to operate while making a left turn. While making a left turn the steering wheel locked and the brakes did not function to stop the vehicle. The vehicle continued to steer to the left and I almost hit another vehicle head on. What stopped my vehicle was the emergency brake system activated by almost hitting the other vehicle head on. They luckily saw me head on and tried to quickly move out the way. This happened two times the second time Thursday, there was a school bus to the left of me my car. I was not making a left turn but on a road that the curve went left and the steering wheel locked in that position. My wheel was locked and failed to stop for about 45 seconds with no car in front to trigger the emergency brakes. Immediately to my left was a school bus. The school bus was not expecting my vehicle to cut them off in this manor, the bus had to make a hard stop to not crash into me. I feel my life and the life of the individuals in the other vehicle and school bus were all put at risk. I towed my car to the dealer and was advised that they did not see any recalls for my vehicle. They also advised me that based on the inspection and the incident details that they would need to replace the steering rack and pinion. My vehicle was operating as it normally did and did not have any system warning prior.

While I was driving my 2012 mb C300 4matic sport sedan in Nov', 2023 with history of regular maintenance, noticed a pretty load knocking noise, shudder and drifting to left a bit when it brakes from the driver's rear side especially on the highways. I took it to our local mechanic who was horrified to report that the sub frame was broken and completely rotten out too specifically rust issue with the rear suspension-rear subframe. He gets other german cars like BMW & Audi even older and more miles in chicago but none have rusted so much as these mb c-class cars. Knowing the dealers wont accept it a manufacturing defect, he was planning to repair it (no chance of wielding that thin metal sheet as the likelihood of breaking it is high). I was surprised to see 2010 chevy impala having a much more robust under the cover protection and no rusting with 115k miles. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

The contact owns a 2022 mercedes-benz C300. The contact stated while driving at unknown speeds, the active brake assist was not functioning properly. The brakes were applied without an object around the vehicle. There were no warning lights illuminated. The local dealer was contacted and scheduled an appointment. The vehicle was not diagnosed or repaired. The manufacturer was not contacted. The failure mileage was approximately 20,000.

See all problems of the 2022 Mercedes Benz C300 🔎.

I have been noticing a hissing sound coming from the brake paddle for almost 3 weeks. Upon some online research I found out it could be a brake booster and there was a recall for the same car brand due to issues with brake booster in past but not included year 2016. Vehicle not inspected yet.

I honestly don’t know how mercedes could have used such a cheap metal mix in their brake lines. Every single C300 made before 2012 is at extreme risk of brake failure every winter, the lines rust very easily and cause ruptures to happen as soon as you need to use your brakes in emergency. If you slam your foot on the brakes for a 2008-2009 mercedes, you are putting your life at risk.

Brake booster vacuum leak causing it to not brake properly. Requires more pedal pressure to come to a stop. Extremely dangerous.

The mercedes just slams on the brakes for no reason. It's happened 3x and is very scary. According to internet posts this is a common problem because of collision assist malfunction.

The contact owns a 2012 mercedes-benz C300. The contact stated that while his wife was driving at an undisclosed speed, she heard an abnormal sound at the rear of the vehicle. The vehicle was taken to an independent mechanic where it was diagnosed that the subframe wheel assembly needed to be replaced. No warning lights were illuminated. The vehicle was repaired however, the contact then stated that he received an unknown manufactured recall for the sub frame assembly where it was then taken to the dealer where the contact was then informed by the technician that the rear brake line had leaked and needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure and the contact was informed that the VIN was not included in a recall. The failure mileage was approximately 120,000.

The contact owns a 2012 mercedes-benz C300. The contact stated while driving at various speeds, extra brake travel time was needed to stop the vehicle. There was no warning light illuminated. The contact had taken the vehicle to an independent mechanic where the vehicle was purchased, and he was informed that the failure was caused by the new brake pads placed on the vehicle. The contact eventually took the vehicle to a dealer and was informed that the fuel tank and brake lines were corroded; and the contact was provided an estimate for the repair. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 96,000.

The contact owns a 2023 mercedes C300. The contact stated that while traveling over a pedestrian crosswalk the emergency braking mode, engaged. The accelerator pedal was applied but the vehicle failed to move. The vehicle went into restricted mode. A Hyundai elantra crashed into the rear of her vehicle. The driver in the Hyundai stated that the brake lights were not illuminated. There was no air bag deployment or fire. A police report was filed. The contact who was occupying the front passenger seat sustained a injury to her neck and medical attention was provided. The vehicle was towed to the local dealer where it was diagnosed that there were no restricted mode codes located. They were unable to duplicate or verify the incident. The vehicle was not repaired. The manufacturer was contacted but no additional assistance was provided. The failure mileage was approximately 2000.

I found out about the mercedes subframe failure issue after having problems on the road, that could have killed me, and being warned not to drive anymore by an authorized repair shop because my vehicle was not safe for me to drive. This has caused many other issues with my cars mechanics due to this defect from the mercedes factory.

The left rear weld of the subframe on my 2012 C300 4matic has rotted through and appears to be a manufacture's part defect. I found out about this issue from a brake inspection and told it is a safety concern, which Mercedes Benzes is aware of but has no recalls for the defect.

First week, the car would take off fast as soon as the brakes were released. Then first time I used the heat there was a crackling sound coming form the side of the center display and it got extremely hot, I was on the fwy driving in the rain. Brakes: intermittently, when braking, the car speeds up as if shifting to n, problematic in the fwy traffic behind another car, sometimes the brake pedal can be heard rattling really lose underfoot, brakes also used to groan when backing up. Electrical: intermittently, the door/trunk lock, side mirror, garage door opener do not work, and the dash displays change by themselves, the worst is the unreasonably hot center display that burns fingers, and becomes untouchable on hot days. Transmission: seems not to work in unison with the accelerator as sometimes the rpm needle hits 3-4 but the car will not speed up or is sluggish. Other: the car intermittently kicks, like being rear ended, it happens at different speeds and stopped or driving, continuing a few times intermittently for a day or two. Twice have taken the car to mbz dealership, one for 2 days, another for 10 days, they said they reset everything and all was fine. The issues are intermittent and hard to duplicate for some one who does not drive the car regularly. The dealership has been great but I do not feel they are able to reveal the problems with the vehicle. The car is like a computer with a virus and sometime gives erratic response.

Discovered a severely "rotted/rusted" rear subframe and one of the passenger side suspension/control arm of the rear passenger side wheel is completely "detached/disconnected" from the rear subframe. During a hard brake, the car will "swing/drift" to the right and is very dangerous and prone to accident/catastrophe. Also, many other 2008-2014 C300 owners already have reported/complaints over the internet. This defect needs to be recalled by the manufacturer.

The subframe and the brake lines are very faulty in this car when it comes to its design. The subframe and brake lines rust easily and are cheaply made for this car. My car break down while driving making it hard to have pressure on the brakes. My incident was around the school area. There were no accidents or collisions involved. It could happen to adults and children. The dealer never confirmed this problem before selling it to me. Another manufacturer told me about this problem. The car showed warning signs like the braking system and brake fluid. The brake fuel was leaking. The problem appeared when I started the car.